A stacked high energy varistor is formed to improve the capability of standard ZOV
or ZOVR high energy varistors. Such varistors provide a much higher maximum pulse
current and absorption energy capability in a much smaller space in comparison to
standard single ZOV of ZOVR varistors.
Stacked varistors are designed to provide secondary surge protection in an outdoor
and service entrance environment. They provide high current (pulse shape 8/20 ìs)
as well as high energy (current pulse shape 10/350 ìs) handling capabilities according
to IEC 61643-11, class I, II and III tests.